The Reason Why My Strict Female Boss Turned Deredere on Me After Turning Back into a High School Student: High School Life Where We Redo Our Mutual Crushes
Light novel series by Tokuyama Gintarou, with illustrations by Yomu.
Premise of the story is exactly as described by the title and 'sub-title'. 'Nuff said.
LN title: 厳しい女上司が高校生に戻ったら俺にデレデレする理由
"The Reason Why My Strict Female Boss Turned Deredere on Me After Turning Back into a High School Student"
Sub-title: 両片思いのやり直し高校生生活
"High School Life Where We Redo Our Mutual Crushes"